CN1800429A - Ultra clean spring steel - Google Patents

Ultra clean spring steel Download PDF

Info

Publication number
CN1800429A
CN1800429A CNA2005101286401A CN200510128640A CN1800429A CN 1800429 A CN1800429 A CN 1800429A CN A2005101286401 A CNA2005101286401 A CN A2005101286401A CN 200510128640 A CN200510128640 A CN 200510128640A CN 1800429 A CN1800429 A CN 1800429A
Authority
CN
China
Prior art keywords
inclusion
quality
cao
sio
steel
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
CNA2005101286401A
Other languages
Chinese (zh)
Other versions
CN100395367C (en
Inventor
杉村朋子
坂本浩一
吉田敦彦
须田澄惠
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Kobe Steel Ltd
Original Assignee
Kobe Steel Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Kobe Steel Ltd filed Critical Kobe Steel Ltd
Publication of CN1800429A publication Critical patent/CN1800429A/en
Application granted granted Critical
Publication of CN100395367C publication Critical patent/CN100395367C/en
Expired - Fee Related legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/02—Ferrous alloys, e.g. steel alloys containing silicon
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/002—Ferrous alloys, e.g. steel alloys containing In, Mg, or other elements not provided for in one single group C22C38/001 - C22C38/60
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/04—Ferrous alloys, e.g. steel alloys containing manganese
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/34—Ferrous alloys, e.g. steel alloys containing chromium with more than 1.5% by weight of silicon
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S148/00—Metal treatment
    • Y10S148/902—Metal treatment having portions of differing metallurgical properties or characteristics
    • Y10S148/908—Spring

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Treatment Of Steel In Its Molten State (AREA)
  • Heat Treatment Of Steel (AREA)

Abstract

Disclosed herein is an ultra clean spring steel which contains inclusions easily elongated and broken into fine particles by hot rolling and which is easily adaptive to cold rolling and yields springs excelling in fatigue characteristics. The spring steel is characterized in that the wire contains oxide inclusions with a sulfur concentration no more than 10 mass% such that no less than 70% (in terms of numbers) of such inclusions, which exist in the outer layer outside one quarter of the diameter of the wire and have a width no smaller than 3 [mu]m, satisfies the formula (1) below, CaO + Al 2 O 3 + SiO 2 + MnO + MgO > 80 (mass%) (1) .

Description

Ultra clean spring steel
Technical field
The present invention relates to a kind of spring steel with excellent fatigue property.This spring steel is prepared the spring that needs excellent fatigue property, as engine valve spring, clutch spring and brake spring.
Background technology
Demand for the higher automobile of the lighter and work output of weight increases, and this demand need develop and can bear heavily stressed engine valve spring and suspension spring.These springs need have good resistance to fatigue and sagging resistance, so that they can support big bearing strength test.Valve spring especially needs to have good fatigue strength, even and use and in conventional steel, to be considered to the best SWOSC-V of fatigue strength (JIS G-3566), this demand also is difficult to satisfy.
Need to be used to the steel wire of the spring of high-fatigue strength need comprise minimum hard non-metallic inclusion therein.This demand is used non-metallic inclusion wherein to be eliminated the clean especially steel of ultimate to satisfy usually.Hardness of steel is high more, because non-metallic inclusion causes steel to stand to break and the possibility of fatigue is high more.Therefore, need stricter minimizing to cause disruptive non-metallic inclusion (amount and size).
Propose various technology, be used for reducing the amount and the size of the hard non-metallic inclusion of steel.For example, non-patent literature 1 given below is mentioned: by making ladle contain fusing point is about 1400～1500 ℃ CaO-Al 2O 3-SiO 2Inclusion just can improve fatigue property, and such inclusion fatigue rupture can not take place.
And patent documentation 1 given below and 2 discloses a kind of ultra-clean steel with excellent fatigue property, it during with hot rolling the abundant extended mode of non-metallic inclusion prepare.
And patent documentation 3 given below and 4 discloses a kind of Si-deoxidized steel, and wherein inclusion is elongated, and this inclusion is by the alkali metal compound size decreases.
In addition, patent documentation 5 given below discloses the technology of inclusion sectional area when reducing fusing point and reduce inclusion content and hot rolling.
Non-patent literature 1
The 126th and 127th Nishiyama Memorial Technical Lecture, JapanIron and Steel Association, 145-165 page or leaf.
Patent documentation 1
The Japanese Patent publication is put down-6-74484
Patent documentation 2
The Japanese Patent publication is put down-6-74485
Patent documentation 3
The open 2002-167647 of Japanese Patent
Patent documentation 4
Japanese Patent 2654099
Patent documentation 5
The Japanese Patent publication is put down-7-6037
Summary of the invention
Up to now, disclosed routine techniques relates to the composition that is easy to elongate the non-metallic inclusion that reduces with size when hot rolling.
Yet these technology have just been noted the average composition of inclusion, and do not consider any variation about inclusion configuration after the hot rolling.Therefore, these technology can not realize satisfying recently the demand of the ultra-clean steel of high-cleanness, high more.
The present invention is in view of aforementioned and finish.Therefore, the purpose of this invention is to provide ultra clean spring steel with excellent fatigability.This purpose is to obtain by the size that fully reduces inclusion when the hot rolling.
Main points of the present invention are ultra clean spring steel, and the characteristic of this spring steel is that it is the oxide inclusion that is not more than 10 quality % that steel wire comprises sulphur content, so that be present in this inclusion that is no less than 70% (in quantitative terms) that the outer skin of steel wire diameter 1/4th and width be not less than 3 μ m formula (1) below satisfying
CaO+Al 2O 3+ SiO 2+ MnO+MgO＞80 (quality %) ... (1)
And be present in two or three compositing areas of (A)～(C) middle qualification below.
(A)SiO 2：40～70％，Al 2O 3：O～20％，CaO：20～60％
(B)SiO 2：30～65％，Al 2O 3：25～50％，CaO：10～30％
(C)SiO 2：10～30％，Al 2O 3：25～50％，CaO：30～55％
(% represents quality %.)
Prerequisite is that " width of inclusion " expression is for observed inclusion on the cross section that comprises the steel wire longitudinal axis, the diameter of each inclusion of on direction, measuring perpendicular to its major axis, content in (A)～(C) (in quality %) is by normalization method, so that three component S iO 2, Al 2O 3Equal 100% with the total content of CaO.
Chemical constitution according to ultra clean spring steel of the present invention is not particularly limited, so long as be getting final product that spring steel designs.Ideal is composed as follows.
C: be no more than 1.2 quality % (not comprising 0%)
Si:0.4～4 quality %
Mn:0.1～2.0 quality %
Al: be no more than 0.01 quality % (not comprising 0%)
Steel with above-mentioned composition can comprise one or more metals that are selected from the group of being made up of Cr, Ni, V, Nb, Mo, W, Cu and Ti.The content of these metals should be preferably as follows.
Cr:0.5～3 quality %,
Ni: be no more than 0.5 quality %, V: be no more than 0.5 quality %,
Nb: be no more than 0.1 quality %, Mo: be no more than 0.5 quality %,
W: be no more than 0.5 quality %, Cu: be no more than 0.1 quality %,
And Ti: be no more than 0.1 quality %.
Any steel capital should preferably comprise the Li of 0.01～20ppm amount.
[effect of the present invention]
The invention provides ultra clean spring steel, therefore described ultra clean spring steel has excellent fatigue property because its inclusion is elongated and becomes littler when hot rolling.
Description of drawings
Figure 1 shows that at CaO-Al 2O 3-SiO 2Ternary phase diagrams in the composition of inclusion in sample number into spectrum 1 distribute.
Figure 2 shows that at CaO-Al 2O 3-SiO 2Ternary phase diagrams in the composition of inclusion in sample number into spectrum 2 distribute.
Figure 3 shows that at CaO-Al 2O 3-SiO 2Ternary phase diagrams in the composition of inclusion in sample number into spectrum 3 distribute.
Figure 4 shows that at CaO-Al 2O 3-SiO 2Ternary phase diagrams in the composition of inclusion in sample number into spectrum 4 distribute.
Figure 5 shows that at CaO-Al 2O 3-SiO 2Ternary phase diagrams in the composition of inclusion in sample number into spectrum 5 distribute.
Figure 6 shows that at CaO-Al 2O 3-SiO 2Ternary phase diagrams in the composition of inclusion in sample number into spectrum 6 distribute.
Figure 7 shows that at CaO-Al 2O 3-SiO 2Ternary phase diagrams in the composition of inclusion in sample number into spectrum 7 distribute.
Figure 8 shows that at CaO-Al 2O 3-SiO 2Ternary phase diagrams in the composition of inclusion in sample number into spectrum 8 distribute.
Figure 9 shows that at CaO-Al 2O 3-SiO 2Ternary phase diagrams in the composition of inclusion in sample number into spectrum 9 distribute.
Embodiment
Be known that any steel wire that carries out gross distortion when hot rolling all should preferably comprise the inclusion that can be elongated and split into molecule in course of hot rolling.Therefore, common practice is to make inclusion have low-melting average composition, so that inclusion is easy to be elongated and be split into molecule when hot rolling.And, run through from being cured to the hot rolled all stage, all adopting and prevent harmful inclusion such as SiO 2,, Al 2O 3, the measure that occurs of lime feldspar, wollastonite and gehlenite.
For the aforementioned idea in the brains, how the shape that the inventor has thought deeply inclusion in heating after solidifying and the course of hot rolling changes, and has studied the composition and the pattern of the single inclusion that influences the fatigue property change from various viewpoints.As a result, find that a large amount of small crystal that forms in the inclusion causes inclusion to be easier to split into molecule before than hot rolling.Find that also the lime feldspar of Xing Chenging, wollastonite and gehlenite are very tiny by this way, so they can not produce detrimentally affect to fatigue property.
Being separated not is sole purpose of the present invention.The phase that importantly causes being separated should be almost harmless or tiny.In other words, if before hot rolling, the composition of inclusion is inappropriate, deleterious SiO can occur 2And Al 2O 3Thereby, fatigue property is produced detrimentally affect.
Therefore, need strict control cogging and hot rolling inclusion before to form.For this reason, need carry out refining, and need the content of strict control aluminium by means of having than the slag of higher basicity in the past.
The present invention should satisfy following requirement.According to the present invention, it is the oxide inclusion that is not more than 10 quality % that steel wire comprises sulphur content, so that be present in this inclusion that is no less than 70% (in quantitative terms) that the outer skin of steel wire diameter 1/4th and width the be not less than 3 μ m formula (1) below satisfying
CaO+Al 2O 3+ SiO 2+ MnO+MgO＞80 (quality %) ... (1)
Noted earlierly stipulated that significant inclusion should have " width that is not less than 3 μ m ".Reason is that width causes repeated stress failure hardly less than the small inclusion of 3 μ m, and to not very significantly influence of fatigue strength.This inclusion of also having stipulated noted earlier should " be present in the skin outside the steel wire diameter 1/4th ".Reason is that the inclusion that is present in this zone influences fatigue property most.
Valve spring ladle oxycompound inclusion and sulfide inclusion thing.The latter is very soft, therefore be easy to be elongated and split into molecule when hot rolling, so it is less to INFLUENCE ON FATIGUE STRENGTH.Therefore, need controlled oxidation thing inclusion, to increase fatigue strength.Why Here it is the present invention relates to oxide inclusion, and does not relate to the cause that contains the sulfide inclusion thing that surpasses 10 quality % sulphur.
Remove CaO, Al 2O 3, SiO 2, outside MnO and the MgO, steel wire comprises inevitable irregular inclusion (as Ti oxide compound and Cr oxide compound) usually.These irregular inclusiones be not will be especially material deeply concerned, as long as their content is restricted.Yet, when their content increases, also can cause repeated stress failure.Here it is, and why the present invention has stipulated its total amount [CaO+Al 2O 3+ SiO 2+ MnO+MgO] those irregular inclusiones of being lower than 80 quality % should not surpass 30% cause of sum.
Regulation steel wire of the present invention should comprise the oxide inclusion that sulphur content is not more than 10 quality %, is present in two or three compositing areas by following (A)～(C) limit so that be not less than this inclusion of 70% (in quantitative terms).
(A)SiO 2：40～70％，Al 2O 3：0～20％，CaO：20～60％
(B)SiO 2：30～65％，Al 2O 3：25～50％，CaO：10～30％
(C)SiO 2：10～30％，Al 2O 3：25～50％，CaO：30～55％
Insert the statement of " being not less than this inclusion of 70% (in quantitative terms) ", this is because if greater than 70% inclusion Be Controlled, then the present invention fully produces the cause of effect of the present invention.There are a variety of inclusiones that cause the disruptive form less than 70% expression.Because the MnO in these inclusiones is harmless, therefore its content is not particularly limited.And MgO specially adds, but derives from refractory materials, so its content is not the problem of being concerned about.
In other words, the present invention allows oxide inclusion to be present in more than in one the compositing area.Possible reason is to occur small crystal in the amorphous inclusion, and these crystal split into molecule when hot rolling.The crystallization inclusion is difficult to break when hot rolling, so they remain in the final product, thereby causes repeated stress failure.Small crystalline produces and means that the generation of macrocrystal is suppressed.This is the possible cause that improves fatigue strength.
For being present in the composition that surpasses the inclusion in the zone, needing fully to control the chemical constitution of steel and the composition (as described below) of inclusion, and need fully control hot-rolled condition.Especially need following cogging Heating temperature and the time before of suitably control.
Heating temperature: 1200～1350 ℃
Heat-up time (or soaking time): greater than 4 hours
Cogging is difficult to produce crystallization under low excessively Heating temperature, and cogging then causes thick crystal under excessive temperature.Although soaking time is generally about 2 hours in the past, soaking time should be preferably more than 4 hours, so that the present invention fully produces its effect.Adopt the long cogging time can cause thick crystal during cogging; Therefore soaking time should be less than 10 hours.Incidentally, if inclusion comprises Li 2O then can reduce heat-up time.
Small crystal in inclusion helps when hot rolling inclusion to be broken becomes molecule.Therefore, the inclusion in stage before importantly control is cast.In crystallisation process, be present in the excessive SiO in the inclusion 2Form thick SiO 2Crystal, and they left behind with thick crystal when hot rolling, thus fatigue strength is produced detrimentally affect.And, excessive Al in the inclusion 2O 3Form thick Al 2O 3Crystal and lime feldspar (CaOAl 2O 32SiO 2), this produces detrimentally affect for fatigue strength.Therefore, control is formed so that various crystal precipitation from homogeneous solution is important.
For this reason, need be at the basicity (CaO/SiO of steel fusion stage working the slag component 2).Desired basicity is in about 0.75～2 scope.
The present invention does not have the chemical constitution of particular restriction steel, because it is to design as the ultra-clean steel of spring steel raw material for helping.Yet, should preferably comprise Si and Mn according to steel of the present invention as reductor, its content is for being no less than 0.1 quality %.But Si should be less than 4%, and Mn should be less than 2%, because if their excessive existence can make steel easily crisp.
Carbon content (as the alkaline constituents of spring steel) should be preferably less than 1.2 quality %.Excessive carbon (greater than 1.2 quality %) can make steel actually become fragile with utilizing.
Aluminium is to be of value to the element of controlling inclusion.Aluminium content should be 0.1～15ppm (quality meter).Excessive aluminium can cause thick Al 2O 3Crystal, and thick Al 2O 3Crystal can cause repeated stress failure.It is desirable to content less than 0.01 quality %.
Steel according to the present invention is made of Fe except that above-mentioned alkaline constituents and unavoidable impurities.It can randomly comprise one or more metals of selecting from the group of being made of Cr, Ni, V, Nb, Mo, W, Cu and Ti.Their desired contents is as follows.
Cr:0.5-3 quality %, Ni: be no more than 0.5 quality %,
V: be no more than 0.5 quality %, Nb: be no more than 0.1 quality %,
Mo: be no more than 0.5 quality %, W: be no more than 0.5 quality %,
Cu: be no more than 0.1 quality % and Ti: be no more than 0.1 quality %.
Can randomly comprise Li according to steel wire of the present invention.Li controls the composition of inclusion effectively or makes and occurs molecule in the inclusion.It has also reduced the viscosity of the pars amorpha of inclusion, makes inclusion easily deformable thus.Li content for this purpose should be preferably about 0.01～20ppm.
Had and be designed to make steel easily deformable when hot rolling thus by incorporating the known technology (as mentioning in the patent documentation 3 and 4 that provides) that Li reduces the inclusion fusing point in the above.Yet these technology are not utilized the crystalline effect.And the small crystal of these Technology Needs can exist in a large number, and the disadvantage of these technology is to add Li can promote thick crystal formationly under the situation that does not have suitable control inclusion, produces detrimentally affect thus.Incidentally, the patent documentation 3 that provides is not above mentioned especially and is added Li, does not mention any about adding the crystallization that Li produces yet.
The present invention is described in more detail with reference to the following examples, but these embodiment will limit the scope of the invention.Under the situation that does not deviate from the scope of the invention, the present invention can carry out changes and improvements.
Embodiment 1
The molten steel of preparation simulation converter steel.For regulating the chemical constitution of steel and slag refining, sneak into various flux.The basicity (as shown in table 2) of suitable working the slag is so that optionally control the composition of inclusion.Like this, several steel samples of chemical constitution shown in the table 1 have been obtained to have.Incidentally, although in steel sample 4～6, Li content is to pass through Li 2CO 3Welding wire feeding mechanism (wire feed) regulate, can finish with in the following method any but in molten steel, add Li.The steel wire that is used for welding wire feeding mechanism can be by Li alloy or Li 2CO 3Combine formation separately or with other alloy material.
(a) form with Li-Al or Li-Si is added by welding wire feeding mechanism; Combine with other alloy; In the molten steel that adds in advance in the ladle, add block (mass); In the TD process, add.
(b) add by the welding wire feed mechanism with the Li form; Combine with other alloy; In molten steel, add block; Add in the ladle in advance; In the TD process, add.
(c) in slag, add Li 2O or Li 2CO 3
(d) add and other alloy bonded Li 2CO 3In molten steel, add block; Add in the ladle in advance; In the TD process, add.
Table 1
The steel mark Chemical constitution (quality %)
C Si Mn Al(ppm) Ni Cr Li(ppm)
A 0.6 2.0 0.7 6 0.2 1.0 --
B 0.55 1.45 0.7 10 -- 0.7 --
C 0.55 1.45 0.7 8 -- 0.7 --
D 0.55 1.45 0.7 5 -- 0.7 0.3
E 0.55 1.45 0.7 4 -- 0.7 0.05
F 0.6 2.0 0.7 5 0.2 1.0 2.0
G 0.55 1.45 0.7 7 -- 0.7 --
H 0.55 1.45 0.7 12 -- 0.7 --
I 0.6 2.0 0.7 6 0.2 1.0 --
Above-mentioned molten steel be cast to the same rate mutually of actual machine under in the refrigerative mould.The gained ingot bar carries out soaking, cogging and hot rolling.Obtaining diameter like this is the steel wire of 8.0mm.Following table 2 shows the basicity of hot-rolled condition and sample number into spectrum 1～9.
Table 2
Sample number into spectrum The steel mark Basicity of slag Hot-rolled condition
1 A 0.84 1280 ℃ * 5h soaking → cogging → 1000 ℃ of following hot rollings
2 B 1.2 1280 ℃ * 5h soaking → cogging → 1000 ℃ of following hot rollings
3 C 1.8 1280 ℃ * 5h soaking → cogging → 1000 ℃ of following hot rollings
4 D 0.79 1280 ℃ * 1h soaking → cogging → 1000 ℃ of following hot rollings
5 E 0.85 1280 ℃ * 1h soaking → cogging → 1000 ℃ of following hot rollings
6 F 0.90 1280 ℃ * 1h soaking → cogging → 1000 ℃ of following hot rollings
7 G 0.81 1280 ℃ * 1h soaking → cogging → 1000 ℃ of following hot rollings
8 H 1.70 1280 ℃ * 1h soaking → cogging → 1000 ℃ of following hot rollings
9 I 0.72 1280 ℃ * 5h soaking → cogging → 1000 ℃ of following hot rollings
The hot rolling steel wire sample detection of the Huo Deing composition of inclusion wherein detects following fatigue strength simultaneously like this.
The composition of inclusion
Each steel wire sample vertically cuts, and polishes the cross section that it comprises its axle.Detect cross section, to pick out 30 oxide inclusions (minor axis is greater than 3 μ m) that are present in outside 1/4th diameters (or radius half).These oxide inclusions are analyzed by EPMA, and analytical results changes into the content of oxide compound.
Fatigue strength
Hot rolling steel wire (8.0mm Φ) is peeled off, patent, cold stretching, oil tempering, the processing that is equivalent to stress relieving, shot peening and stress relieving.Obtaining measuring diameter is that 4.0mm and length measurment are the testing plate of 650mm.This testing plate is carried out crooked test with Nakamura-formula rotoflector fatigue tester under following condition.
Stress: 880MPa (specified)
Speed of rotation: 4000～5000rpm
Bend cycles number of times: 2 * 10 7
Calculate the fracture ratio by following formula for those samples of rupturing owing to inclusion.The fracture sample detection appears at the size of the inclusion on the fracture surface.
Fracture ratio=[A/ (A+B)] * 100%
(wherein A represents the sample number that ruptures owing to inclusion, and B represents 2 * 10 7The sample number that does not have fracture after the bend cycles).
Table 3 shows the fracture ratio and the size of observed inclusion on fracture surface.
Following table 4～12 show the composition of inclusion in each steel wire sample.Fig. 1～9 show by the SiO according to result shown in table 4～12 2-Al 2O 3The composition of the inclusion that-CaO ternary phase diagrams is represented distributes.
Table 3
Sample number into spectrum The steel mark Fracture is than (%) The overall dimension of inclusion on the fracture surface
1 A 6 22.4
2 B 15 25.0
3 C 12 24.5
4 D 1 14.3
5 E 3 15.2
6 F 0 13.2
7 G 36 33.5
8 H 39 41.2
9 I 53 47.1
Table 4
The composition of inclusion (quality %) in the sample number into spectrum 1
CaO Al 2O 3 SiO 2 MnO MgO
12.2 35.7 48.2 3.7 0.3
30.1 4.6 61.9 2.0 1.3
11.1 32.7 53.0 1.7 1.5
12.3 35.4 49.1 2.9 0.4
13.7 36.0 47.8 1.9 0.5
12.4 35.9 47.1 2.4 2.4
11.8 35.0 49.6 3.6 0.0
13.7 35.8 47.3 2.7 0.5
16.9 37.0 44.2 0.7 1.2
15.1 39.0 45.2 0.7 0.0
12.9 35.0 46.9 2.7 2.4
33.2 1.8 58.9 3.1 2.9
13.8 38.3 44.5 3.4 0.0
10.5 35.1 49.6 4.8 0.0
12.5 31.7 50.5 2.1 3.2
12.9 34.7 46.2 5.0 1.1
15.9 33.7 46.2 2.7 1.5
13.0 35.5 47.8 2.3 1.3
15.6 31.8 48.0 2.7 1.9
14.4 36.9 46.1 1.5 1.0
12.7 37.2 47.4 1.8 0.9
15.8 35.2 46.9 1.9 0.2
13.3 35.5 48.2 1.5 1.5
33.6 7.7 55.2 0.7 2.9
35.5 6.0 54.8 2.0 1.6
11.0 32.6 50.2 4.4 1.9
12.5 34.5 50.0 3.0 0.0
30.0 5.5 60.2 1.2 3.2
32.2 4.3 59.2 1.4 2.9
38.1 5.3 53.6 1.0 2.0
Table 5
The composition of inclusion (quality %) in the sample number into spectrum 2
CaO Al 2O 3 SiO 2 MnO MgO
14.5 42.9 40.2 0.0 2.4
15.1 48.2 34.9 1.8 0.0
17.5 43.1 34.7 1.4 3.3
12.3 43.6 42.1 0.8 1.2
18.1 42.8 36.5 0.5 2.1
16.8 40.9 40.1 0.2 2.0
19.5 39.4 35.9 2.8 2.4
11.3 38.8 44.6 2.1 3.2
14.6 37.8 43.7 0.7 3.2
19.4 37.4 38.9 1.2 3.1
18.7 36.8 39.1 2.7 2.7
24.6 33.3 35.5 3.9 2.7
17.6 33.5 45.6 1.3 2.0
18.6 32.9 46.1 2.4 0.0
22.5 31.7 44.1 0.5 1.3
19.2 29.0 46.7 1.8 3.3
19.5 31.5 40.3 6.0 2.7
33.7 41.9 22.5 1.9 0.0
35.0 40.5 20.3 2.7 1.5
35.2 38.4 24.6 1.8 0.0
34.9 37.2 23.2 1.5 3.2
35.0 36.7 26.0 2.3 0.0
40.5 36.6 21.1 0.7 1.1
39.1 34.7 21.1 2.7 2.4
36.5 34.8 25.2 3.1 0.4
42.3 33.6 20.1 2.7 1.3
36.0 32.1 24.0 5.6 2.3
40.1 32.7 22.8 1.5 2.9
45.1 30.0 21.0 3.4 0.5
45.0 30.4 22.5 2.1 0.0
Table 6
The composition of inclusion (quality %) in the sample number into spectrum 3
CaO Al 2O 3 SiO 2 MnO MgO
55.6 0.0 41.3 1.8 1.3
52.3 27.1 17.2 2.3 1.1
54.3 2.3 40.1 1.7 1.6
53.3 26.1 17.6 2.0 1.0
53.6 0.1 43.3 1.5 1.5
57.2 0.5 42.3 0.0 0.0
55.1 1.4 42.6 0.7 0.2
51.6 25.3 20.5 0.3 2.3
54.9 0.3 41.2 3.3 0.3
46.8 10.0 41.6 1.2 0.4
52.1 0.5 44.1 3.3 0.0
55.9 0.3 41.2 1.4 1.2
50.4 4.3 42.5 2.3 0.5
47.6 3.0 43.3 5.6 0.6
53.9 27.5 17.3 1.0 0.3
53.1 28.4 15.2 1.2 2.1
53.6 28.3 15.6 1.3 1.2
53.6 30.2 13.9 1.2 1.1
52.2 28.5 16.4 1.7 1.2
50.1 25.5 21.3 1.8 1.3
53.1 25.0 18.7 2.1 1.1
51.6 28.0 15.7 2.2 2.5
51.0 25.1 20.1 2.2 1.6
50.1 27.6 17.5 3.5 1.3
48.1 27.0 18.2 4.3 2.4
48.2 7.0 43.7 1.1 0.0
52.1 29.7 13.9 3.3 1.0
51.3 34.6 11.5 0.3 2.3
55.9 0.1 40.2 3.6 0.2
50.3 4.5 42.1 1.9 1.2
Table 7
The composition of inclusion (quality %) in the sample number into spectrum 4
CaO Al 2O 3 SiO 2 MnO MgO
16.5 35.7 45.9 1.9 0.0
18.2 34.5 44.7 2.5 0.1
16.3 33.1 45.8 1.4 3.4
11.9 31.0 50.2 2.8 4.1
24.0 29.7 39.6 4.3 2.4
20.1 28.3 46.5 0.3 4.8
19.6 26.5 48.2 1.9 3.8
20.2 26.0 47.7 3.5 2.6
22.7 25.0 46.9 3.4 2.0
22.5 28.0 44.5 4.0 1.0
47.7 1.5 49.9 0.8 0.1
37.9 3.5 56.1 1.3 1.2
34.0 8.3 52.9 1.7 3.1
42.6 3.0 51.4 2.0 1.0
35.3 4.9 55.1 2.1 2.6
36.9 2.4 55.1 3.4 2.2
30.7 4.9 58.1 4.1 2.2
18.0 33.0 45.2 2.6 1.2
14.6 30.1 49.6 4.2 1.5
14.8 33.2 48.7 2.0 1.3
18.1 30.0 48.6 3.3 0.0
17.3 32.2 47.5 1.8 1.2
11.9 39.5 45.4 2.2 1.0
11.8 39.4 45.0 3.8 0.0
17.3 36.1 45.4 1.2 0.0
16.0 36.1 43.5 2.5 1.9
17.4 35.6 43.4 2.2 1.4
22.7 31.7 44.5 0.5 0.6
14.4 39.3 43.0 2.1 1.2
21.3 37.3 41.4 0.0 0.0
Table 8
The composition of inclusion (quality %) in the sample number into spectrum 5
CaO Al 2O 3 SiO 2 MnO MgO
30.7 18.9 47.3 1.9 1.2
18.5 35.5 43.5 2.2 0.3
40.2 4.6 51.8 1.7 1.7
31.4 16.5 49.1 2.7 0.3
39.1 1.3 57.3 1.1 1.2
40.1 2.8 55.1 1.7 0.3
16.2 32.2 46.3 2.2 3.1
32.4 3.1 58.1 3.1 3.3
36.2 5.2 54.7 1.5 2.4
18.1 36.2 43.1 2.4 0.2
23.6 30.0 44.6 1.6 0.2
40.1 1.4 55.4 2.1 1.0
16.4 32.8 47.5 2.1 1.2
37.1 3.7 55.3 1.3 2.6
38.2 9.6 50.3 1.8 0.1
13.9 33.9 48.9 0.0 3.3
16.3 27.3 53.1 1.2 2.1
37.1 2.6 53.1 2.1 5.1
45.2 0.9 50.1 1.2 2.6
15.1 34.1 49.3 0.6 0.9
19.8 25.0 50.1 1.9 3.2
37.4 5.9 53.2 1.9 1.6
15.1 38.9 43.5 0.3 2.2
17.2 31.5 48.1 2.2 1.0
23.4 32.7 40.1 1.9 1.9
20.2 23.6 53.6 1.4 1.2
12.6 29.5 53.4 2.5 2.0
25.9 30.2 43.8 0.1 0.0
26.4 27.5 45.1 0.6 0.4
24.6 27.8 46.9 0.4 0.3
Table 9
The composition of inclusion (quality %) in the sample number into spectrum 6
CaO Al 2O 3 SiO 2 MnO MgO
34.5 10.6 50.5 3.4 1.0
15.1 26.5 53.9 1.3 3.2
40.1 0.6 55.8 2.2 1.3
38.4 8.6 49.7 1.8 1.5
40.8 6.9 49.3 2.0 1.0
38.2 0.9 55.2 3.1 2.6
17.7 29.2 51.6 1.5 0.0
33.3 8.4 55.3 1.9 1.1
36.3 3.0 56.8 1.3 2.6
14.5 25.8 54.3 3.3 2.1
15.3 38.5 43.2 1.5 1.5
21.5 28.9 47.6 1.7 0.3
35.1 3.3 57.6 1.9 2.1
18.7 27.7 50.1 1.2 2.3
34.8 4.4 54.3 3.4 3.1
39.3 0.4 56.7 2.1 1.5
12.3 29.6 55.2 0.3 2.6
16.3 30.5 50.9 2.1 0.2
37.8 4.1 55.1 0.8 2.2
22.3 25.2 47.9 2.3 2.3
18.2 28.0 51.3 1.3 1.2
40.1 3.8 52.3 1.7 2.1
13.2 28.3 52.1 3.3 3.1
18.1 34.2 45.7 0.7 1.3
20.3 25.1 50.2 1.2 3.2
19.1 26.0 45.2 5.6 4.1
19.4 28.4 48.3 1.9 2.0
20.1 33.0 44.8 0.0 2.1
17.5 30.7 48.7 2.1 1.0
19.4 27.3 50.1 1.3 1.9
Table 10
The composition quality % of inclusion in the sample number into spectrum 7)
CaO Al 2O 3 SiO 2 MnO MgO
40.5 1.8 51.4 4.7 1.6
35.8 2.6 51.7 5.5 4.4
33.5 4.4 55.2 3.8 3.1
24.4 11.6 50.2 6.1 7.7
27.4 13.0 53.6 5.6 0.4
25.8 14.3 51.2 6.1 2.6
30.2 14.9 47.2 5.6 2.1
27.6 15.2 51.5 3.3 2.4
28.0 15.9 52.3 3.6 0.2
26.7 16.6 55.3 1.1 0.3
23.5 15.8 53.6 4.7 2.4
25.8 17.8 47.5 1.2 7.7
25.9 18.9 50.4 4.2 0.6
26.5 21.0 50.7 1.3 0.5
30.1 21.5 42.3 5.5 0.6
28.8 20.0 46.9 4.3 0.0
26.5 20.1 46.7 3.1 3.6
26.7 21.0 48.3 2.7 1.3
27.1 21.9 49.2 1.3 0.5
27.9 21.5 45.5 4.6 0.5
23.3 22.2 48.6 5.6 0.3
29.1 23.2 44.3 3.2 0.2
24.4 23.2 48.2 0.9 3.3
20.4 22.5 47.9 4.1 5.1
23.5 23.2 45.5 6.1 1.7
28.9 25.6 45.2 0.0 0.3
18.1 28.8 49.6 3.2 0.3
18.5 38.0 43.5 0.0 0.0
18.6 37.3 40.8 1.7 1.6
12.9 38.4 47.0 1.3 0.4
Table 11
The composition of inclusion (quality %) in the sample number into spectrum 8
CaO Al 2O 3 SiO 2 MnO MgO
18.6 54.5 19.3 7.6 0.0
21.2 54.8 22.8 0.9 0.5
16.9 55.0 25.1 1.2 1.8
19.7 50.9 25.2 1.4 2.8
27.6 51.0 17.6 0.6 3.2
17.5 48.4 25.4 6.0 2.7
20.7 51.3 25.9 2.1 0.0
24.6 50.2 21.9 0.8 2.5
24.1 45.9 23.7 5.2 1.1
23.9 46.8 25.0 0.5 3.8
25.1 47.8 24.8 0.2 2.1
23.9 45.6 25.4 1.9 3.2
27.0 44.7 23.2 1.8 3.3
28.6 44.6 22.3 2.5 2.4
27.6 42.9 24.3 1.9 3.3
30.2 42.7 21.9 1.8 3.4
24.5 40.8 26.4 3.0 5.3
28.3 40.7 22.7 7.9 0.4
26.8 42.0 26.8 0.2 4.2
29.1 41.1 23.9 2.7 3.2
29.4 41.4 24.6 0.8 3.8
29.5 40.8 24.2 3.6 1.9
30.6 40.9 23.4 0.6 4.5
30.4 41.2 24.2 2.1 2.1
30.7 42.1 25.0 0.2 2.0
25.6 40.6 28.6 1.9 3.3
32.1 40.5 22.4 0.9 4.1
25.9 40.8 29.0 2.0 2.3
28.9 38.8 26.8 1.0 4.5
26.5 39.2 30.4 1.6 2.3
Table 12
The composition of inclusion (quality %) in the sample number into spectrum 9
CaO Al 2O 3 SiO 2 MnO MgO
14.0 8.2 75.0 1.5 1.3
13.2 11.0 73.2 0.0 2.6
17.2 8.9 73.0 0.8 0.1
18.1 10.6 70.0 0.3 1.0
19.2 2.0 73.2 3.3 2.3
18.3 3.9 76.4 1.2 0.2
7.2 7.3 82.1 3.3 0.2
24.2 3.1 69.5 2.1 1.1
13.4 3.4 77.4 4.2 1.6
12.6 30.9 53.5 2.0 1.0
14.9 26.1 54.1 3.4 1.5
17.2 22.7 53.9 2.7 3.5
19.1 24.0 52.4 2.2 2.3
13.2 27.8 53.1 3.3 2.6
14.4 30.1 52.1 1.4 2.0
32.1 9.4 55.1 2.3 1.1
32.4 2.3 56.7 4.1 4.5
34.2 3.1 58.9 1.9 1.9
32.4 6.0 57.6 3.1 0.9
29.6 8.4 56.4 3.2 2.4
29.4 11.1 57.2 1.8 0.5
31.2 2.1 62.3 2.9 1.5
30.1 4.3 63.3 1.7 0.6
28.4 7.7 60.1 2.5 1.3
31.2 2.3 59.1 3.9 3.5
13.2 27.0 55.3 1.9 2.6
12.1 26.0 56.1 3.4 2.4
13.4 22.2 55.4 1.3 7.7
5.3 3.2 86.1 2.2 3.2
7.6 7.8 80.1 3.8 0.7
Infer following result from above.Sample number into spectrum 1～3 therefore show sufficient fatigue strength, and the composition of inclusion is divided into two zones owing to suitably controlled basicity of slag and hot rolling under conditions suitable.Sample 4～6 has been also owing to suitably controlled basicity of slag and added Li except that the short period of time soaking, and shows sufficient fatigue strength, and the composition of inclusion is divided into two zones.
On the contrary, sample number into spectrum 7 and 8 is owing to short soaking time and inadequate being separated, and the result that performance is gone on business on Fatigue Test, and the composition of inclusion is not divided into two zones.Sample number into spectrum 9 is because low basicity of slag (produces high SiO with being separated 2The inclusion of content) on Fatigue Test, shows the result who goes on business.

Claims (4)

1. ultra clean spring steel, its characteristic is that it is the oxide inclusion that is not more than 10 quality % that steel wire comprises sulphur content, so that be present in that the outer skin of steel wire diameter 1/4th and width be not less than 3 μ m in quantitative terms be no less than such inclusion of 70% formula (1) below satisfying
CaO+Al 2O 3+ SiO 2+ MnO+MgO＞80 (quality %) ... (1)
And described 70% the such inclusion of in quantitative terms being no less than also is present in below in two or three compositing areas that limit in (A)～(C),
(A)SiO 2：40～70％，Al 2O 3：0～20％，CaO：20～60％
(B)SiO 2：30～65％，Al 2O 3：25～50％，CaO.：10～30％
(C)SiO 2：10～30％，Al 2O 3：25～50％，CaO：30～55％
Wherein, % represents quality %,
Prerequisite is: " width of inclusion " represents the diameter of each inclusion, this diameter is to be used on the cross section that comprises the steel wire longitudinal axis observed inclusion to measure on the direction perpendicular to its major axis, and the content in (A)～(C) is in quality %, by normalization method, so that three component S iO 2, Al 2O 3Equal 100% with the total content of CaO.
2. as the ultra clean spring steel of claim 1 qualification, it is formed by the steel that comprises following component:
C: be no more than 1.2 quality % (not comprising 0%)
Si:0.4～4 quality %
Mn: 0.1～2.0 quality %
Al: be no more than 0.01 quality % (not comprising 0%).
3. as the ultra clean spring steel of claim 1 qualification, it also comprises one or more metals that are selected from the group of being made up of Cr, Ni, V, Nb, Mo, W, Cu and Ti.
4. as the ultra clean spring steel of claim 1 qualification, it comprises the Li of 0.01～20ppm amount.
CNB2005101286401A 2004-11-24 2005-11-24 Ultra clean spring steel Expired - Fee Related CN100395367C (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2004339328A JP4347786B2 (en) 2004-11-24 2004-11-24 High cleanliness spring steel
JP2004339328 2004-11-24

Publications (2)

Publication Number Publication Date
CN1800429A true CN1800429A (en) 2006-07-12
CN100395367C CN100395367C (en) 2008-06-18

Family

ID=35999447

Family Applications (1)

Application Number Title Priority Date Filing Date
CNB2005101286401A Expired - Fee Related CN100395367C (en) 2004-11-24 2005-11-24 Ultra clean spring steel

Country Status (6)

Country Link
US (1) US7429301B2 (en)
EP (1) EP1662016B1 (en)
JP (1) JP4347786B2 (en)
KR (1) KR100712786B1 (en)
CN (1) CN100395367C (en)
DE (1) DE602005009909D1 (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105316591A (en) * 2015-03-14 2016-02-10 洛阳辰祥机械科技有限公司 Preparation method for high-performance spring
CN105463312A (en) * 2015-12-28 2016-04-06 合肥中澜新材料科技有限公司 Preparation method for anti-scratch automobile sound-reducing box
CN105940132A (en) * 2014-01-29 2016-09-14 株式会社神户制钢所 Steel wire for springs having excellent fatigue properties, and spring
CN107083523A (en) * 2017-06-02 2017-08-22 太仓市龙华塑胶有限公司 A kind of handware steel

Families Citing this family (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8613809B2 (en) 2006-06-09 2013-12-24 Kobe Steel, Ltd. High cleanliness spring steel and high cleanliness spring excellent in fatigue properties
JP4150054B2 (en) * 2006-06-21 2008-09-17 株式会社神戸製鋼所 FORGING STEEL, PROCESS FOR PRODUCING THE SAME AND FORGED PRODUCT
KR101146842B1 (en) * 2006-12-28 2012-05-16 가부시키가이샤 고베 세이코쇼 Silicon-killed steel wire material and spring
CN101982555B (en) * 2006-12-28 2013-05-08 株式会社神户制钢所 Si killed steel wire material having excellent fatigue property and spring
JP4163239B1 (en) 2007-05-25 2008-10-08 株式会社神戸製鋼所 High cleanliness spring steel and high cleanliness spring with excellent fatigue characteristics
JP5342827B2 (en) * 2007-11-19 2013-11-13 株式会社神戸製鋼所 Spring steel and spring with excellent fatigue characteristics
JP5323416B2 (en) * 2007-11-19 2013-10-23 株式会社神戸製鋼所 Spring steel and spring with excellent fatigue characteristics
US8900381B2 (en) 2007-11-19 2014-12-02 Kobe Steel, Ltd. Spring steel and spring superior in fatigue properties
JP5329272B2 (en) * 2009-03-19 2013-10-30 株式会社神戸製鋼所 Spring steel
JP5937973B2 (en) 2013-01-15 2016-06-22 株式会社神戸製鋼所 Si-killed steel wire rod having excellent fatigue characteristics and spring using the same
JP5935944B2 (en) * 2013-04-24 2016-06-15 新日鐵住金株式会社 Low oxygen clean steel and low oxygen clean steel products
EP3346020B1 (en) 2015-09-04 2020-07-29 Nippon Steel Corporation Spring steel wire and spring
CN105779881B (en) * 2016-05-04 2017-10-10 唐山钢铁集团有限责任公司 A kind of production method of high-carbon spring steel steel band
CN105970081A (en) * 2016-05-23 2016-09-28 安徽鑫宏机械有限公司 Casting method for anti-corrosive and abrasion-resistant composite check valve body
CN108842116A (en) * 2018-06-15 2018-11-20 邯郸慧桥复合材料科技有限公司 A kind of high-speed rail brake disc and its production method

Family Cites Families (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0674485B2 (en) 1985-10-26 1994-09-21 新日本製鐵株式會社 High cleanliness steel
JPH0674484B2 (en) 1985-10-26 1994-09-21 新日本製鐵株式曾社 High cleanliness steel
JPH076037B2 (en) 1986-12-01 1995-01-25 新日本製鐵株式会社 Spring steel with excellent fatigue strength
JP2654099B2 (en) 1988-06-21 1997-09-17 株式会社神戸製鋼所 Manufacturing method of clean steel
JPH0234748A (en) * 1988-07-22 1990-02-05 Kobe Steel Ltd Silicon killed steel having excellent fatigue resistance
JPH046211A (en) * 1990-04-25 1992-01-10 Kobe Steel Ltd Production of steel wire for spring having excellent fatigue strength
JPH0674485A (en) 1991-09-30 1994-03-15 Toyotomi Co Ltd Drain water processing structure of cold air dehumidifying machine
JP2713046B2 (en) 1992-08-27 1998-02-16 ダイキン工業株式会社 Installation frame structure of embedded air conditioner
JPH06145895A (en) * 1992-10-30 1994-05-27 Kobe Steel Ltd High sterength and high toughness steel wire rod, extra fine steel wire using the same steel wire rod, production therefor and straded steel wire
JPH06158226A (en) * 1992-11-24 1994-06-07 Nippon Steel Corp Spring steel excellent in fatigue characteristic
JPH06306542A (en) * 1993-04-28 1994-11-01 Kobe Steel Ltd Spring steel excellent in fatigue strength and steel wire for spring
JPH076037A (en) 1993-06-16 1995-01-10 Matsushita Electric Ind Co Ltd Instruction decoding device
JP2000047935A (en) * 1998-07-31 2000-02-18 Nec Software Kobe Ltd High speed memory access processor
JP3504521B2 (en) 1998-12-15 2004-03-08 株式会社神戸製鋼所 Spring steel with excellent fatigue properties
JP3719131B2 (en) 2000-11-27 2005-11-24 住友金属工業株式会社 Si deoxidized steel excellent in fatigue strength and method for producing the same

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105940132A (en) * 2014-01-29 2016-09-14 株式会社神户制钢所 Steel wire for springs having excellent fatigue properties, and spring
CN105940132B (en) * 2014-01-29 2018-01-30 株式会社神户制钢所 The steel wire material for spring and spring of excellent in fatigue characteristics
CN105316591A (en) * 2015-03-14 2016-02-10 洛阳辰祥机械科技有限公司 Preparation method for high-performance spring
CN105463312A (en) * 2015-12-28 2016-04-06 合肥中澜新材料科技有限公司 Preparation method for anti-scratch automobile sound-reducing box
CN107083523A (en) * 2017-06-02 2017-08-22 太仓市龙华塑胶有限公司 A kind of handware steel

Also Published As

Publication number Publication date
US20060108027A1 (en) 2006-05-25
JP4347786B2 (en) 2009-10-21
EP1662016A1 (en) 2006-05-31
CN100395367C (en) 2008-06-18
US7429301B2 (en) 2008-09-30
JP2006144105A (en) 2006-06-08
DE602005009909D1 (en) 2008-11-06
KR20060058031A (en) 2006-05-29
EP1662016B1 (en) 2008-09-24
KR100712786B1 (en) 2007-04-30

Similar Documents

Publication Publication Date Title
CN1800429A (en) Ultra clean spring steel
CN1169992C (en) Steel for mechanical structure
CN101158011B (en) Martensitic free cutting stainless steel
CN105121680B (en) The spring steel of excellent in fatigue characteristics and its manufacture method
CN1255569C (en) Martensitic stainless steel
JP4658695B2 (en) Forging steel and crankshaft with excellent hydrogen cracking resistance
CN1306056C (en) Low-carbon free cutting steel
CN1143903C (en) High-strength steel wire with anti-strain-ageing-brittle and anti-longitudinal-crack and manufacture method thereof
JP5163241B2 (en) Case-hardened steel
CN1950532A (en) Seamless steel pipe and method for production thereof
CN1827819A (en) Steels for high-strength springs excellent in cold workability and quality stability
CN1659297A (en) Steel excellent in machinability
CN1078912C (en) High strength and high tenacity non-heat-treated steel having excellent machinability
JP5163242B2 (en) Case-hardened steel
JP6515327B2 (en) Bearing steel and method of manufacturing the same
CN1846010A (en) Non-heat treated steel for soft-nitriding
JP2009041046A (en) Steel for induction hardening, and its manufacturing method
CN1950533A (en) Steel for mechanical parts, method for producing mechanical parts from said steel and the thus obtainable mechanical parts
JP5206459B2 (en) Case-hardened steel
JP2005054216A (en) Steel material superior in machinability and fatigue characteristics, and manufacturing method therefor
JP2005273010A (en) Toothed gear and manufacturing method therefor
JP2005126817A (en) Steel part for machine structure having excellent fatigue property and machinability, method for manufacture thereof, and stock for induction hardening
JP2005060723A (en) Crankshaft having excellent bending fatigue life, and its production method
JP2018165403A (en) Steel for carburizing having excellent low cycle fatigue strength and machinability, and carburized component
JP2009108357A (en) Non-heat treated steel for martensite type hot-forging, and hot-forged non-heat treated steel part

Legal Events

Date Code Title Description
C06 Publication
PB01 Publication
C10 Entry into substantive examination
SE01 Entry into force of request for substantive examination
C14 Grant of patent or utility model
GR01 Patent grant
CF01 Termination of patent right due to non-payment of annual fee
CF01 Termination of patent right due to non-payment of annual fee

Granted publication date: 20080618